December 1, 2005 Microbiologists tested 14 hand-hygiene agents -- everything from soap and alcohol rubs to plain old tap water -- against hardy bacteria and viruses applied to the hands of 62 volunteers. The study found that soap and water did the best job of removing germs. Just 10 seconds of washing soap and water was enough to knock off more than 90 percent of microbes.
CHAPEL HILL--Cold and flu season is fast approaching and before you start sniffling and sneezing, you should know the number one way scientists say to fight germs before they become a full-blown cold.
Mom was right -- and now she's backed up by science. Microbiologists at the University of North Carolina in Chapel Hill tested 14 hand-hygiene agents. Everything from soap to alcohol rubs to plain old tap water was tested against hardy bacteria and viruses applied to the hands of 62 volunteers.
Emily Sickbert-Bennett, an epidemiologist at UNC School of Public Health, says, "Really the best thing was plain soap and water." Soap isn't designed to kill bacteria. It acts as a surfactant to lift dirt off of surfaces so it can be rinsed away just like when you use dish washing liquid to remove grease off of dishes.
"We really think it's probably due to the just the physical washing off of those germs," Bennett says. Researchers also discovered just 10 seconds of washing is enough to knock off more than 90 percent of the germs known as microbes. "We know that 10 seconds is effective, and we can focus more on compliance, rather than increasing the length of time you wash your hands."
David Weber, an infectious disease researcher at UNC School of Medicine says, "Because it's not only a droplet disease, meaning three feet, but it is also a contact and touching disease as well." For times you aren't in close contact with a sink, the study revealed alcohol rubs do almost as well, and for parents who have a tough time selling soap -- so did plain old tap water.
Hospitals and health care facilities are paying close attention to this study. That's because health care associated infections rank in the top five causes of death, with an estimated 90,000 deaths each year in the U.S.
BACKGROUND: Nothing works better at getting rid of disease-causing viruses than simply washing one's hands with old-fashioned soap and water. That advice comes from the largest and most comprehensive scientific study ever done to compare the effectiveness of hand hygiene products.
THE STUDY: Scientists at the University of North Carolina at Chapel Hill studied how effective 14 different hand hygiene agents performed in reducing bacteria and viruses from the hands after a 10-second exposure. Previous studies had participants clean their hands for 30 seconds, even though most people, including busy health care personnel, don't spend that much time washing up. Subjects first cleaned their hands, which were then exposed to a harmless bacterium and a virus comparable to disease-causing organisms. Then the subjects cleaned their hands with various agents, after which the scientists measured how much of the bacteria and virus remained. Among the viruses studied is one that causes the common cold, along with viruses that cause hepatitis A, acute gastroenteritis, and other illnesses.
THE RESULTS: The study showed that after a short exposure time of 10 seconds, nearly all the hand hygiene products reduced 90 percent of bacteria on the hands. But waterless alcohol-based hand wipes only removed about 50 percent of bacteria from the subjects' hands.
The American Society for Microbiology contributed to the information contained in the TV portion of this report.
Editor's Note: This article is not intended to provide medical advice, diagnosis or treatment.